The present disclosure relates to mouthpieces configured for use with inhalers.
Asthma patients administer bronchodilators and glucocorticosteroids with inhalation devices or inhalers. Effective inhalation devices produce an aerosol of medication with a significant dose of particles in the so-called respirable range that enters the lower airways. Inhalation devices generally include a canister that holds medicament under pressure and a boot portion in which the canister is seated. The boot portion includes a mechanism, which causes the canister to release some of the medicament in aerosol form.
Metered-dose inhalers (MDIs) and pressurized metered-dose inhalers (pMDIs) are widely used by asthma patients. Nonetheless, even when these types of inhalers are used correctly, only about 10% to 20% of the nominal per puff dose reaches targeted airways. Due to the rate and pressure at which medicament is expelled from an MDI or pMDI, much of the medicament impinges upon oral and throat tissues and does not reach the patient's lungs, as intended.
Various techniques have been proposed in an effort to improve inhaled drug delivery. One technique, termed the “open-mouth” technique, positions an egress opening of the MDI or pMDI about 2 inches from the patient's mouth. The medicament is then sprayed directly into the patient's open mouth while the patient inhales deeply and slowly. With the open-mouth technique, the medicament enters the patient's mouth and lungs at a slower rate and under less pressure, so that more medicament reaches the deep lungs. The open-mouth technique, however, is often not recommended by medical practitioners. Frequently, patients who attempt this technique fail to achieve consistent, repeatable and successful dosing. Many patients, for example, mis-aim the inhaler or inhale too quickly.
In some cases, a spacing device or holding chamber is combined with the MDI or pMDI to slow the velocity of the aerosol and allow more time for the propellant to evaporate. Some spacing devices hold the medicament aerosol discharged from the pMDI in suspension for approximately 2-3 seconds, which allows the patient to inhale more medicament at a slower rate. Unfortunately, some patients using spacing devices continue to experience problems, such as failing to receive sufficient medicament dosage because the patient has inhaled before actuating the pMDI, or waiting too long after actuation before inhaling.
Solutions to problems associated with inhalation devices and ineffective inhaled drug delivery continue to be sought.